The 39 Articles of Religion begin with the absolute basic questions of reality: who is God? This is the heart of the definition of theology, explaining who and what God is.
The liturgy of the Anglican tradition, as ordered in the Prayer Book, is an excellent companion to such basic statements of theology as are found here in these five Articles. The doctrine of the Trinity (spelled out Article 1) is expressed in nearly every prayer and collect in the liturgy. The doctrine of Christ being both entirely God and entirely Man (spelled out in Article 2) is described especially in the collects associated with the days and week abutting Christmas and Easter. His descent and resurrection (as taught in Articles 3 and 4) are affirmed in prayer and worship throughout Holy Week. The doctrine of the Holy Spirit (as put forth in Article 5) finds its particular echoes in the prayers associated with the Day of Pentecost. Thus, these first five Articles do not stand in a vacuum of dry intellectual teaching, but are closely linked with the life of worship as well.
Furthermore, the teaching of these Articles on the basics of God’s identity is affirmed universally among Protestants and Papists alike. None of these beliefs were of real controversy during the Reformation, and they all remain cornerstones of fundamental agreement among all Christians. Together, they also summarize the majority of the content of the Creeds, which are also believed by all Christians. Thus, Articles 1 through 5 are especially valuable for identifying the true faith from counterfeits – all Christians affirm these teachings; thus all who reject them are deceivers or deceived.
The only possible exception in here is the phraseology in Article 5, that the Holy Spirit proceeds “from the Father and the Son.” The original text of the Nicene Creed says only that the Spirit proceeds “from the Father,” and that is what the Easter Orthodox Church teaches to this day. Depending upon how this distinction is understood, there can be some sharp disagreements between East and West. Further discussion of this issue is addressed in my comments for Article 5, though a thorough analysis is beyond the scope of this project (and, indeed, outside of the purpose of the Articles).